Press.



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APPLICATION UPHAIVI.

PRESS.

HLED AuG.22.1911.

Patented 1101.211916.

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PRESTON UPHAIVI, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO INTERNATIONAL PAVEMENT COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF CON- NECTICUT.

PRESS.

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Specification of Letters Patent.

Patented oet. sa, raie..

Application led August 22, 1911. Serial No. 645,402.

vcitizen of the United States, residing in Bos ton, Suffolk county, State of Massachusetts, have invented an Improvement in lPresses, of which the following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

My invention, one embodiment of which is illustrated in the accompanying drawing and herein described, relates to certain improvements in presses which improvements possess many Jfeatures of novelty and invention which are useful either in combination with each other as disclosed, or as used separately in any type of press. One of these features is my pressure creating and pressure transmitting system. Another is my improved construction for operating my mold opening, filling, and closing means.

Many other features of novelty will be eX- plained hereinafter.

The drawing shows a diagrammatic view of the press. In the embodiment of my invention disclosed in this drawing the driving pulley 1, driven by a belt from any suitable source of power, is shown keyed on the shaft 2, to which is keyed the pinion 3. rIhe pinion 3 meshes with the gear 4 keyed on the timing shaft 5 so that said belt and gearing constitute one type of motor for said shaft 5. The timing shaft 5 isA provided with a crank 6. A connecting rod 7 connects said crank with a displacing plunger 8 which reciprocates, in a part of a cham-4 ber 9 of the hydraulic cylinder 10. In lieu of the crank 6, I may, without departing from the spirit of my invention, use any other suitable actuator, preferably one having a fixed throw, as, for example, an eccentric or cam, altering the connection with the plunger 8 to correspond. The hydraulic cylinder 10 is provided with pressure responsive means herein shown as a ram 11 although a diaphragm may be used without departing from the spirit o'f my invention. The receptacle or chamber between the displacing plunger y8 and the ram 11 is :filled with a normally substantially constant body or fixed quantity of liquid. It will readily be seen that revolution of the timing shaft 5 will produce reciprocation of the ram 1l and'that the pressure applied to the dis' placing plunger 8 will be multiplied when transmitted to the ram 11. in the same'ratio as the respective areas of the displacing plunger and ram. In order that excessive resistance to compressive movement of the ram may not stall the timing shaft or break any of the parts, and also herein to provide a dwell or period of high compression, I have provided automatic pressure determining, limiting or controlling means. This also acts as compensating means to compensate for movement of the actuator after the material under compression is compressed to the desired degree. In the embodiment herein disclosed, comprises a pressure determining ram 12, reciprocable in a cylinder 13 interposed between the ram 11 and the pressure receiving abutment 23. The cylinder 13 contains a substantially constant body of liquid and coperates with a pressure determining or controlling plunger l2, I have herein shown the pressure determining or relief plunger 12a as resisted by or receiving pressure from a piston 14 in a fluid pressure cylinder 15 though any yielding method of imparting resistance to my controlling plunger, such as a spring, weight,

or the like may be used. Steam or other fluid pressure is admitted to one end of this cylinder in such a way as to hold the controlling plunger 12a in its inmost position with relation to the cylinder 13, except when a predetermined resistance is opposed t0 compressing movement of the ram 12. When this occurs, the pressure determining or controlling plunger 12a will be forced back from the cylinder 13 against the pressure of the fluid in the fluid pressure cylinder 15. The cylinder 13, the plunger 12a and the fluid pressure cylinder 15 and the amount of liquid in the cylinder 13 are all so proportioned that the pressure at which the controlling plunger 12a begins to recede may be normally reached before the displacing plunger 8 reaches the end of its stroke. They are also so proportioned that the controlling plunger will, under normal conditions, merely recede in its chamber dur- `ing the further displacing stroke of the displacing plunger without allowing any liquid to escape. In view of the above describedV pressure determining or compensating mechanism I may use any yielding compensator preferably interposd between the ram and the mold plunger.

The pressure system, one form of which is herein disclosed, is designed primarily to coperate with an automatically operating mold, for the compression of blocks, bricks, tiles and the like, made from asphaltic or other plastic material. .I h'ave shown in the drawings a mold containing member 17 having a mold cavity, and a plunger 19 operable used, I have shown a.' bulkhead 23, containing the filling neck 21 and the mold cover or pressure receiving block 22. -It is immaterial however whether the mold .cover is i moved relative to the mold or whether'the old is moved relative to the mold cover. The bulkhead is held from upward movement by bolts 18 connected to thehydraulic cylinder 10.

In. the vembodiment shown, it is necessary that the sliding mold member 17 should be automatically movable into three positions respectively, for filling as shown in the drawing, for pressing with the pressure receiving block l22 covering the mold and for ejection with the mold entirely removed from under the neck and pressure receiving member. So '40 far as I am at present advised, in all presses heretofore constructed which require the -mold to be mved into three positions relative to the mold rover, movement of the Amold 1n one dlrectlon at least has been occasioned by positive-mechanical means as distinguished from fluid pressure means. One object of the present invention is to provide fluid pressure mold operating means for prol ducing all such movements.A In the embodiment herein vdisclosed, I accomplish this by the use of two fluid pressure cylinders.

v Of these, one shown at 24 contains the piston 25 operating the piston rod 26, the piston 'p25 having stroke limiting means herein shown as the tail rod 27, the link 28 and the 'fixed pin 29 attached to any suitable and convenient support. I may use a crank or anyl other suitable stroke limitingA device without departing from the spirit of my invention.. In the embodiment of my invention shown, the piston rod -26l is not attached to the 'sliding mold but abuts against it.

Another fluid pressure cylinder 30 is pro-i vided with -a piston 31, a` iston rod 32 connected tothe sliding mol and the taill rod 33 provided with stroke. limiting 'meansl Vshaft 5 which preferably also operates as the crank shaft of the press are mounted any suitable cams or other well known mechanical devices or means. Of these, one, through any suitable connection, a part of which is shown at 38, operates the slide valve 39. in the valve chest 40 which controlsA the inlet and outlet of steam or fluid pres-'sure fromthe cylinder 24. Fluid pressure is preferably admitted to one end of this cylinder only. Any suitable inlet may admit steam to the valvechest 40, and any suitable exhaust port may serve to exhaust steam from the cylinder 24. Another cam or the like on the shaft 5 through any suitable connection, a part of which is shown at 43, operates the slide valve 44 in the steam chest 45'. This slide'valve 44 controls the admission and exhaust of steam from the opposite ends of the cylinder 30. The exhaust pipe 46 is preferably provided with a safety valve 47 so that when one end of the cylinder is exhausting, a relatively low pressure will still be maintained therein. This serves to maintain a low pressure in the end of the cylinder 30 when the steam pressure in the cylinder 24 is moving the mold containing memberfinto pressing position and prevents any momentum acting to continue movement of said mold containing member after the piston 25 has completed its stroke. After the compression of the block in the mold and the uncovering of the mold, I provide ejection or mold emptying means preferably operated by iiuid pressure. In the embodiment of .my invention herein disclosed, I accomplish this by a fluid pressure operated ejecting cylinder 48 having a piston 48a and the piston rod 48b operating through the connecting rod 49 on the bell crank 50 pivoted on the shaft 51 which operates to lift the plunger 19 to eject the block. The point to which the plunger` is to be raised by this fluid pressure cylinder is determined 'by any suitable stroke limiting device herein shown as lugs having set screws 52, which may be adjusted to allow the plunger to be elevated to such a height only as to be flush with the top of the mold containing member 17. Steam is admitted and exhausted from the ejecting cylinder 48 by means of a slide valve 53 located in any suitable valve chest 54. AThe slide valve 53 is operated through any suitable connectingmechanism, typified by a Vcam or any other suitable device located on the timing shaft 5.

- The operation of the press is as follows: In the position shownin the drawing, the mold has iust been filled. Fluid pressure is now admitted to the end 57 of the fluid pressure cylinder 24 by movement of the slide valve 39. The pressure in the cylinder 30 being low, mold member 17 is pushed by the rod 26 until the pin 29 stops the link 28. As explained before, if desired, a relatively low pressure may be maintained in the cylinder 3() to prevent the momentum of the mold member from carrying it past the des ired pressing position. The crank 6 which revolves clockwise now starts the displacing plunger 8 on its inward travel starting the ram 11 on its upward travel. This continues until the displacing plunger 8 has completed its inward stroke. When the predetermined pressure is reached, on the contents of the mold, the pressure determining or controlling plunger 12@L responds, permitting the ram 12 to recede in the cylinder 13 and allows the displacing plunger 8 to finish its inward stroke without substan tial further movement of mold plunger 19. lit is manifest, in the embodiment of my inventionherein shown, that normally from the instant the displacing plunger causes movement of the pressure determining means until the latter resumes its starting position, after the displacing plunger has made the necessary part of its return stroke, a substantially uniform predetermined pressure will be maintained uponthe contentsof the mold'through the compressing plunger, the intervening pressure determining means and the main ram 11. This pressure will be thus applied for a period which is believed to be approximately twice the length of time that a uniform pressure can be maintained upon any positively actuated hydraulic press of like capacity of the safety valve, liquid expulsion type. This increased dwell or period during which a high compression is maintained is valuable to effect a more perfect compression of the material in the mold. The controlling plunger and the inwardpressure applied thereto should be so proportioned to the other elements of my pressure transmission and determining system that it will not normally allow any liquid to escape from thecylinder 13 but will take up the surplus movement of the displacing plunger by receding from the cylinder 13. The pressing operation being completed when the displacing plunger has receded sufficiently to relieve all pressure from the material in the mold, it is necessary to move the mold from under the pressure receiving member 22 so that the compressed material may be ejected therefrom.

To perform this, steam is admitted to the 'timed together. f system obviates the necesslty for constantly tion such that fluid pressure is admitted to the end 59 of the cylinder 48. This, throughy the connections before explained, causes the 4block to be ejected from the mold. The

-ters with the mold 18, the fluid pressure in the cylinder 24 having first been exhausted by the action of the slide valve 39. The fluid pressure isc now exhausted from the end 59 of the cylinder 48 and if necessary, other fluid pressure may be admitted to the opposite end of the cylinder 48 to assist'in allowing the plunger 19 to fall and cause the mold to be again filled with unpressed material from the neck 21. Any suitable device as shown at 61 may be used to vary the downward stroke of the plunger and hence the amount of material admitted to the mold and the thickness of the resultant block.

As will be readily seen by the construction shown in the present embodiment of my in-A vention, the pressure creating means is actuated independently of my mold operating means. By this arrangement, in case of any obstruction to the sliding head moving or block ejecting means, the pressing power which is very great is not effective to break any of the parts, 'yet they are all relatively My hydraulic transmission supplying new liquid as is the case with the usual types of mechanically actuated .hydraulic presses which are supplied with safety valves to permit escape of the liquid when a predetermined pressure is reached. By my system, the main pressure ram is synchronously responsive to every movement of the displacingplunger throughout its fixed travel. The construction shown, as before ex lained also prolongs the dwell yduring w ich the material is subjected to its maximum pressure, because the maximum pressure is maintained during a part of the stroke of the displacing plunger in both directions. T preferably provide a replenishing pump 62 adapted to replace any liquid which may leak through the packing or otherwise escape from the chambers 9 While I have shown and described an improvement in mold operating mechanism, such improvement is not herein claimed, but is dominated by claims in my co-pending application, Serial No. 645,7 94, filed August 21, 1911.

Having thus described one embodiment of invention is not limited to the constructions and combinations herein shown and described but what I desire to claim broadly by Letters Patent is set forth in the following claims. l

Claims:

1. A block forming press having a chamber containing a substantially fixed amount of pressure multiplying and transmitting' ,means forsaid liquid; a fixed throw actuator for said displacing means; a ram responsive to movement of said liquid by said displacing means; a reciprocatory pressing element contiguous to the material to be pressed; and pressure limiting means interposed between said ram and said pressing element.

3. A block forming press comprising in combination a chamber containing a substantially liXed amount of pressure'multi plying and transmitting liquid; displacing means for said liquid; a fixed throw actuator for said displacing means; a ram responsive to movement of said liquid by said displacing means; a reciprocatory pressing element contiguous to the material to be pressed; and elastic Huid actuated pressure limiting means interposed between said ram and said pressing element.

4. A block forming press comprising in combination a chamber containing a substantially fixed amount of pressure multiplying and transmitting liquid; displacing means for said liquid; a iXed throw actuator for said displacing means; a ram responsive to movement of said liquid by said displacing means; a reciprocatory pressing element contiguous to the material to be pressed; and hydraulic pressure limiting means interposed between said ram and said` pressing element.

5. In a block forming hydraulic press a pressing element contiguous to the material to be pressed; a main ram; a fixed-throw liquid displacing plunger; a receptacle between said ram and said displacing means containing a substantially constant body and fixed quantity of pressure transmitting liquid; an auxiliary hydraulic ram having its coperating receptacle containing a Xed quantity and constant body of liquid; and an'ela'stic iiuid sustained displacing plunger,

said auxiliary hydraulic ram and coperat-y Ving parts being operatively interposed between said mam ram and said pressing element. l

' In testimony jwhereof, IA have signed my name to this specification, in the presence of two `subscribing witnesses.

p PRESTON UPHAM. Witnesses:

ROBERT H. KAMMLER, F. IRENE CHANDLER. 

